Transmission structural unit

ABSTRACT

A gear constructional unit with a gear housing is provided. In order to make the effective diameter of the inner gear elements greater, as well as to ensure a simple assembly and exchangeability of the individual gear elements, for example coupling arrangements and planetary wheel sets, there are provided at least two bar-form guide elements, which extend, as viewed in an axial direction, over at least a part of the axial extent of the cylindrical inner space, on which a large number of gear elements are mounted in fixed position with respect to the housing. The bar-form guide elements are located adjacent to the cylindrical inner space, outside of a zone having the greatest dimension of the cylindrical inner space relative to the gear housing dimension, and are arranged in recesses in the gear housing which are connected with the inner space.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a gear constructional unit in particular withan essentially cylindrical interior space and bar form guide elementsfor mounting gear elements.

2. Description of the Related Art

Gear constructional units are known in a large number of executions.These can be executed as

a) a mechanical gear component

b) a hydrodynamic-mechanical compound gear component.

Hydrodynamic-mechanical compound gear components are known, for example,from the following publications:

Buksch, M: ZF five-gear automatic gears for passenger cars, VDI report878 (1991)

Mitescko, G: Four-gear planetary gears for passenger cars with thehydrodynamic torque converter in the power branch, Automobilindustrie(1995) 5, pages 597-602

Klement, W.: The development of the DIWA gears, Verkehr und Technik(1997) 7, pages 301-303

Gear components which have either only purely mechanical transmissioncomponents or else consist of a combination of a hydrodynamic converteror of a hydrodynamic coupling with a downstream mechanical gear set,have as a rule a housing which in respect to its inner contour isadapted to the shape of the individual gear elements and to theirconnection to the housing and they have, as a rule, interior insetswhich undesirably reduce the inside diameter. For example, one knowngear uses a threading of the gear elements onto six rods which areallocated to the interior space of the gear circumferentially at uniformintervals. This makes possible, to be sure, a very simple assembling ofthe components or gear elements, but the arrangement of the six bars incircumferential direction with constant spacing between two bars, aswell as the number of these rods considerably reduces the insidediameter of the gear system, since the upper bars in installationposition determine the structural height and therewith also the possibleusable planetary diameter.

Underlying the invention, therefore, is the problem of creating apossibility for the formation of gear components, especially gearhousings, with which in firmly prescribed installation as high aspossible torques can be transmitted. In detail, there, emphasis is to begiven to a reduction of the constructive and above all of themanufacturing technical expenditure as well as a minimizing of therequired number of components.

BRIEF SUMMARY OF THE INVENTION

According to the invention the gear component, which comprises a gearhousing and has a substantially cylindrical interior space, has at leasttwo bar-form elements for the tying-on of gear elements in radialdirection with respect to the gear axis, or in peripheral direction. Thebar-form guide elements extend there essentially over a range in whichthere are arranged the gear elements provided for the tying-on. Thebar-form guide elements are assigned to the cylindrical interior spaceand are arranged outside of this, in which the allocation occurs in suchmanner that the bar-form guide elements are provided outside of a zonewhich, as viewed in installation position of the gear, corresponds tothe greatest dimension of the interior space in elevation direction ofthe gear component.

This means that none of the guide elements is arranged in installationposition above the greatest dimension of the interior space in elevationdirection, in the gear housing, but rather they are in the zonesformerly more intensive in material for the gear housing, with anessentially quadrangular gear external contour with cylindrical interiorspace.

Under a further aspect of the invention there occurs there anarrangement of the bar-form guide elements with respect to thecylindrical interior space in a zone which is bounded by theinstallation position

Under a further aspect of the invention there occurs there anarrangement of the bar-form guide elements with respect to thecylindrical interior space in a zone which is bounded by the minimal andmaximal dimensions of the cylindrical interior space. This means thatthere does not occur an arrangement directly above the greatestdimension in elevation direction, or underneath the lowest dimension ofthe cylindrical interior space in elevation direction, on the symmetryline of the cylindrical interior space running in elevation direction,as viewed in installation position. This offers the advantage that thehousing builds relatively in elevation direction and therefore doesjustice optimally to the increasingly raised demands on the utilizationof the available construction space.

With the solution according to the invention, therefore, the insidediameter or the inside contour of the gear housing can be madenoticeably greater with constant installation measures for the gearcomponent. By the guidance of the bar-form guide elements in therecesses which are connected with the cylindrical interior space, thecylindrical interior space can be utilized completely by the gearelements in respect to their radial extent. For example, with executionof the gear elements as a lamellar coupling the surface describable bythe cross section surface of the interior space can serve morecompletely as possibly usable friction surface. Since the bar-form guideelements do not collide with the interior space, the other rotating gearelements, for example planetary wheel sets, can also be laid out in suchmanner that the entire interior space is completely utilized in radialdirection. This leads to the result that because of the diameterincrease with the same construction length, a greater torque can betransferred. It is possible to dispense with additional interior insetsfor the bearing, which reduce the diameter of the interior space. Thesuspension on the, bar-form guide elements prevents a twisting of theindividual gear elements in circumferential direction and, in addition,limits the movability in radial direction with respect to the gear axis.

Compulsorily required are only two bar-form elements; at most four arerequired and preferably four bar-form guide elements are set in. Thearrangement occurs in this case, as viewed in the cross section of thegear housing, in the corners zones, which (cross section) is describableby the section amount between the cylindrical interior space and atheoretically generatable square Q_(theoretical) with a side dimensiongreater than or equal to the diameter of the interior space, thetheoretically generatable square Q_(theoretical) and the interior spacehaving identical axes of symmetry. In this case, especially with arectangular housing with cylindrical interior space, thematerial-intensive corner zones are used for the reception of the guideelements. The guide elements are guided there in recesses that areconnected with the cylindrical interior space. Preferably thearrangement of the guide elements, however, occurs always symmetrically.This offers the advantage that the production expenditure for the gearelements and the gear housing can be minimize, as can also theassembling expenditure, since it is not necessary to take care of howthe individual recesses or the passage openings on the gear elementshave to be formed for the reception of the guide elements. Furthermore,the hosing base body can be made with the recesses independently of thelatter actual installation position.

As gear elements there can be regarded, for example, brake arrangementsin the form of lamellar brakes, partitions, actuating elements forbraking or coupling devices, for example in the form of cylinders,pistons or cylinder-piston units, lamellae carriers or the like.

The bar-form elements preferably have over their axial extent, a like orconstant diameter. This offers the advantage that the assembling cantake place independently from the installation direction of the bar-formelements. There is conceivable also, depending on the formation of thetotal gear component, the use of bar-form elements with differentdiameter over the axial extent. In this case, however, as a rule, anassembling will occur as a rule from two sides.

By bar-form elements there are meant there guide elements the profile ofwhich is constructed as a solid or hollow profile, or constitutes acombination of the two.

The guide elements, further, depending on the connection, can functionas shaft or axles.

It is conceivable, for example, to execute a guide element as a hollowaxle which encloses, for example, a shaft for the drive of additionalunits or an axle.

The cross section of the bar-form guide element is preferably circular.There are conceivable, however, also executions with tetragonal crosssection or arbitrary cross section.

In regard to the bearing of the bar-form guide elements the followingvariants can be used:

a) Bearing on the housing in housing wall projections, for example atthe beginning and/or end of the housing

b) Bearing in intermediate walls, which are threaded onto the guideelements

c) Suspended bearing on a wall projection or an intermediate wall, forexample on the face sides of the gear, for example over covers

d) Bearing over wall projections (lugs)

The gear component can be constructed as a purely mechanical gearcomponent. In this case each bar-form guide element extends preferablyover the entire axial extent of the gear component. In the execution ofthe gear component as a hydrodynamic-mechanical compound gear, thebar-form guide element is provided with an axial length whichcorresponds to the axial extent of the mechanical gear part, withrespect to the total gear component. It is always required, however,that the axial extent of the guide elements corresponds to the axialextent of the gear element supported on this.

A further possibility for the bearing of the bar-form elements lies inusing the housing cover. In the especially preferred forms of execution,however, this possibility is dispensed with, in order to keep thehousing cover free from forces, especially axial forces.

In an especially preferred gear component unit devices for the resettingof actuating elements of the lamellar brake- and/orcoupling-arrangements are led through the bar-form guide elements.Between the two friction surface-carrying elements which are couplablewith one another indirectly by frictional closure, there is provided atleast one spring storage arrangement, which is likewise led over thebar-form guide elements and is laid out in such manner that ongeneration of the frictional closure between the frictionsurface-carrying elements and the intermediate element the springstorage arrangement is pre-stressable. By friction surface carryingelements there are meant there the elements which are couplable with oneanother over an intermediate element. In each case a frictionsurface-carrying element and a friction surface-carrying intermediateelement form, on pressing-on a friction surface pair. By frictionsurface there is meant there the surface or the surface zone whichparticipates in the friction closure. The friction surface there can bea component of the friction surface carrying element or of theintermediate element or it can be allocated to this as a separateelement, for example in the form of a covering. The friction surface orthe surface zones functioning as friction surface of a frictionsurface-carrying element or intermediate element can be generated,further, by a coating or surface treatment. The function of frictionsurface-carrying elements can be taken over there both by the outer aswell as also by the inner lamellae. By reason of the effect of thespring storage unit between the individual friction surface-carryingelements, on relaxation of the actuating element in each case there actsan oppositely directed force on the friction surface-carrying elements,so that a rapid separation becomes possible with complete release of thefrictional closure. The spring storage arrangements, therefore actindirectly, over a friction surface-carrying element, upon the actuatingelement. The actuating element itself can be executed, for example, as apiston, which preferably can be acted upon hydraulically orpneumatically. This possibility of arranging the spring storage elementsbetween the friction surface-carrying elements offers the advantage thatthe dimensions of the friction surface carrying elements in radialdirection are no longer dependent on the size of the inner dimensions ofthe gear housing under consideration for the required construction spacefor the device, at least for the indirect resetting of the actuatingelements. The arrangement of spring storage units between the frictionsurface-carrying elements connectable with one another over anintermediate element offers the advantage of a space-saving execution ofthe resetting device, especially of the piston of a cylinder/piston unitin axial direction, which again affects the gear length in use of thebrake arrangements in lamellar construction in a gear. In regard to thearrangement of the spring units between the friction surface-carryingelements, a large number of possibilities are conceivable:

a) Arrangement of spring units between each of the two adjacent frictionsurface-carrying elements;

b) Arrangement of the spring unit in force-flow direction between thefriction surface-carrying elements in the zone of the force introduction(in the zone of the in each case outside-lying friction surface-carryingelements with respect to the installation position of the brakingarrangement in a gear component);

c) Arrangement of the spring unit between two friction surface-carryingelements adjacent to one another with respect to the axial extent of thebraking arrangement in the middle zone of the latter;

d) Arrangement according to b) in combination with c);

e) Arrangement of spring units in correspondence to the possibilitiesdescribed in a) to d);

f) Combination of e) with the possibilities a) to d).

As spring storage units there are preferably used spring elements whichhave a characteristic line characteristic with an essentially constantforce flow over a certain spring excursion. Preferably, therefore, cupsprings are used. The execution of the spring units as a shaft springring is likewise thinkable. The actuating arrangements can be executedas cylinder-piston arrangements, which are actable upon hydraulically orpneumatically. In correspondence to the arrangement of the piston forthe resetting device over the friction surface-carrying elements,especially lamellae on the piston are active, either in the zone of thepiston surface or outside of the piston surface. In regard to theformation of the piston there are distinguished executions with

a) one piston

b) a plurality of pistons.

The appertaining cylinders can be formed there by a cylinder-carryingelement or by a plurality of cylinder-carrying elements. Thispossibility for the piston resetting offers the advantage of a minimalspace required in radial as well as in axial direction. In combinationwith the solution according to the invention there is given thepossibility of creating a gear component with the possibility of hightorque transmission with the structural height remaining constant, orwith a reduced structural height.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The solution according to the invention is explained in the followingwith the aid of the figures. In these, the following is represented:

FIG. 1a is a schematic diagram of the inventive gear unit;

FIG. 1b is a section view of the inventive gear unit of FIG. 1a takenalong line A—A of FIG. 2; and

FIG. 2 is a section view of the inventive gear unit of FIG. 1a takenalong line B—B of FIG. 1b.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 explains the solution according to the invention by way ofexample, with the aid of a certain gear type in axial section. The gearconstruction unit is executed as hydrodynamic-mechanical compound gear1.

The hydrodynamic-mechanical compound gear 1 comprises a firsthydrodynamic gear part 2 in the form of a hydrodynamic speed/torqueconverter 3 and a second mechanical gear part 4. The mechanical gearpart 4 comprises a mechanical speed/torque converter 5 and a group setengaged downstream to this in force flow direction. The mechanicalspeed/torque converter 5 is executed as a modified Ravigneaux-planetarywheel set. This comprises a first planetary wheel set 7 and a secondplanetary wheel set 8, which have a planetary wheel carrier 9 used incommon. This establishes the coupling between a gear element of thefirst and of the second planetary wheel set. The first planetary wheelset 7 comprises a sun wheel 7.1, planetary wheels 7.2 and a hollow wheel7.3. The second planetary wheel set 8 comprises a sun wheel 8.1,planetary wheels 8.2 and a hollow wheel 8.3.

The group set 6 comprises at least one planetary wheel set 10, which hasa sun wheel 10.1, planetary wheels 10.2, a hollow wheel 10.3 and a web10.4.

The hydrodynamic-mechanical speed/torque converter 3 comprises a turbinewheel T, a pump wheel P, a first guide wheel L1, and a second guidewheel L2, and it is covered by a housing 11. The pump wheel P isconnected with a gear input shaft E, which is couplable at leastindirectly with a drive device serving for the driving, preferably witha flywheel 12 of an internal combustion engine in such manner that theforce from the flywheel 12 is transferred to the pump wheel P. Theturbine wheel T is joined untwistably with a turbine wheel shaft 13. Inorder to use the advantages of the hydrodynamic torque transfer withbridging coupling, which in the following would be:

automatic stageless setting-in of the relation between the drive- andoff-drive-speed corresponding to the load on the off-drive side

availability of the maximum torque for a starting operation with highacceleration;

possibility of head lead-off by outside or surface cooling

separation of the hydrodynamic speed/torque converter from theoff-drive, especially from the vehicle at low drive speeds and transferof a low residual torque, so that a choking of the drive device from theoff-drive side is not possible

wear-free power transfer

and simultaneously . . . (Sc. to avoid) the disadvantages of ahydrodynamic power transmission, which essentially has an often nosufficiently attainable efficiency, in order to be able to work with ahydrodynamic gear alone, since power loss constituents that comprisefriction and impact losses reduce the transferrable total power, and thetransformation ranges achieved are often insufficient for the vehicleuse, the hydrodynamic speed/torque converter 3 is used only in the lowergear stages, preferably only during the starting operation, for thepower transfer. For the improvement of the transmission efficiency,therefore, the hydrodynamic speed/torque converter 3 is taken out of thepower transmission, preferably by bridging. For this purpose, betweenthe turbine wheel T and the flywheel 12 or the gear input shaft there isarranged a bridging coupling 14.

The first guide wheel L1 is arranged on the turbine side between theturbine wheel T and the pump wheel P and is borne by a freewheeling. Thefirst guide wheel L1 is untwistably connectable with a first guide wheelshaft 15, there being provided between the first guide wheel L1 and theguide wheel shaft 15 a freewheeling 16, which is laid out in such mannerthat it transfers a torque onto the first guide wheel shaft 15 when thefirst guide wheel L1 turns in opposite direction, i.e. in a rotationdirection opposite that of the turbine wheel T, and which runs withoutload when the first guide wheel L1 rotates in normal direction, i.e. inthe same direction of rotation as the turbine wheel T. The second guidewheel L2 is arranged between the turbine wheel T and the pump wheel Pand is couplable, over a second guide wheel shaft 17, with the housing11. Between the second guide wheel L2 and the second guide wheel shaft17 there is arranged a freewheeling 18, by means of which the secondguide wheel L2 can be coupled with the second guide wheel shaft 17, butonly when the second guide wheel L2 rotates in a direction opposite thatof the turbine wheel T.

The pump wheel P is untwistably connected with a pump wheel shaft 19,which is turnably borne over a bearing in the housing 11.

For the execution of the individual gear stages and the design of theindividual gears, switching elements are allocated to the individualelements of the hydrodynamic-mechanical compound gear system 1. Betweenthe hydrodynamic gear part 2 and the mechanical gear part 4 there areprovided a first coupling arrangement K1 and a first braking arrangementB1.

The turbine wheel T and the turbine wheel shaft untwistably couplablewith it, are coupled with the sun wheel 8.1 of the second planetarywheel set 8 of the mechanical speed/torque converter 5. Preferably theturbine wheel T and the sun wheel 8.1 of the second planetary wheel set8 are arranged on a common shaft, here the turbine wheel shaft 13; theturbine wheel shaft 13 carries there also the coupling (clutch) disk 20of the first coupling K1. The first coupling K1 has, further, a couplingdisk 21, which is coupled with the first guide wheel shaft 15. Further,the first glide wheel L1 is connectable, over the first guide wheelshaft 15, with the sun wheel 7.1, of the first planetary wheel set 7 ofthe mechanical speed/torque converter 5. The coupling disk 21 isconnected with the first guide wheel shaft 15. The first guide wheelshaft 15 is executed as a hollow shaft, which encloses the guide wheelshaft 13 in circumferential direction.

With the coupling covering 21 of the first coupling K1 there isconnected a preferably disk-form element 22, and forms with this aconstructive unit on the outer circumferential zone 23 of which thefirst braking arrangement B1 can engage. The first braking arrangementB1 serves there for the fixing into place of the first guide wheel L1over the guide wheel shaft 15 and/or of the first sun wheel 7.1 of thefirst planetary wheel set 7 of the mechanical speed/torque converter 5.Further switching elements, here the switching elements in the form ofbraking arrangements B2 and B3 are allocated to the individual planetarywheel sets 7 and 8 of the mechanical speed/torque converter 5. In thecase represented the second braking element B2 is allocated to thehollow wheel 7.3 of the first planetary wheel set 7, and the thirdbraking element B3 is allocated to the hollow wheel 8.3 of the secondplanetary wheel set 8 of the mechanical speed/torque converter 5. Thecoupling of the mechanical speed/torque converter 5 with the gear inputshaft E over the hydrodynamic speed/torque converter 3 or its bridgingover the bridging coupling 14, occurs thereby by coupling of the turbinewheel T or the turbine wheel shaft 13 with a first gear element of themechanical speed/torque converter 5 and of the first guide wheel L1 witha further second gear element of the mechanical speed/torque converter5. As first gear element of the mechanical speed/torque converter 5there functions here the sun wheel 8.1 of the second planetary wheel set8. As second gear element there functions the sun wheel 7.1 of the firstplanetary wheel set 7. The shafts coupled with the two sun wheels 7.1and 8.1, here the first guide wheel shaft 15 and the turbine wheel shaft13, function as input shafts of the mechanical speed/torque converter 5.A further third gear element is connected over the group set 6 with thegears output shaft A. As third gear element there functions theplanetary carrier 9, which is used in common by both planetary wheelsets 7 and 8. The third gear element of the mechanical speed/torqueconverter 5 is connected with the input, which is formed by a first gearelement of the group set 6. Preferably this connection is realized overan untwistable coupling of the third gear element of the mechanicalspeed/torque converter 5 and the first gear element of the group set 6.Both are preferably arranged on a common connecting shaft 24. The firstgear element of the group set 6 is formed by its planetary carrier 10.4.A second gear element of the group set 6 is untwistably joined with thegear output shaft A of the hydrodynamic-mechanical compound gear system1. As second gear element there functions, in the case represented, thehollow wheel 10.3 of the planetary wheel set 10 of the group set 6.While the mechanical speed/torque converter 5 serves for the executionof three gear steps in combination with the hydrodynamic speed/torqueconverter 3, in the case represented six gear steps can be obtained bythe combination of the hydrodynamic speed/torque converter 3 (and) ofthe mechanical speed/torque converter 5 with the group set 6. For thispurpose there are allocated to the group set 6 in each case a furthercoupling arrangement, here the second coupling arrangement K2 and afurther braking arrangement, here the fourth braking arrangement B4. Thefourth braking element serves there for the fixing into position of thesun wheel 10.1 of the group set 6. The second coupling arrangement K2makes possible the rigid coupling between the planetary carrier 10.4 andthe sun wheel 10.1 of the planetary wheel set 10 of the group set 6.

In the cut represented in FIG. 1b, from a possible axial section of thegear component 1 it is to be seen how individual gear elements which arefastened to or borne on the housing are fastened to this housing 11 inthe manner of the invention. The individual braking arrangements B1 toB4 are executed in laminar construction. These comprise in each case atleast two friction surface-carrying elements which are joined with oneanother by friction closure over a friction surface-carryingintermediate element. The friction surface-carrying elements, there, aredesignated as follows for the individual braking arrangements:

B₁: B₁₁, B₁₂, B_(1n)

B₂: B₂₁, B₂₂, B_(2n)

B₃: B₃₁, B₃₂, B_(3n)

B₄: B₄₁, B₄₂, B_(4n)

The intermediate elements are designated in each case with B_(1z),B_(2z), B_(3z) and B_(4z). There, the friction surface-carrying elementsB_(1n) to B_(4n) form the outer lamellae. The fixed positioning of theouter lamellae occurs over the bar-form guide elements 40. These extendpreferably at least over the axial extent of the mechanical gear part 4.The housing 11 has in this section an inside diameter 4 essentiallyconstant over the axial extent. Preferably, as represented in FIG. 2,four bar-form guide elements 40.1 to 40.4 are provided, which arearranged, in circumferential direction in the gear housing 11, forexample with constant spacing to one another. The gear housing 11itself, for example, at least in the zone which receives the mechanicalgear part 4, is formed in such manner that it has a substantiallycylindrical inner cross section. Preferably the gear housing, as viewedin axial direction, has a substantially constant inside diameter in thezone of the mechanical gear part 4. The inside diameter is designed insuch manner that essentially the rotating gear elements and componentscan rotate freely, utilizing the maximally possible construction space.The individual guide element 40 is preferably executed in one piece, butcan also consist of several sections. In the unmounted state of themechanical gear part 4, the inner part of which is designated here with41, is essentially empty. For the assembling, first the bar-form guideelements are brought into the corresponding positions or suspended ontothe gear housing in a corresponding manner, and the individual gearelements are successively threaded on these guide elements incorrespondence to the desired arrangement. From the separation point T,all the components of the mechanical gear part can be threaded one afteranother to the housing cover 42 in the assembling. This offers theadvantage that with the threading-on technique and the constant insidediameter the individual components in the mechanical gear part 4 can beexchanged among one another, and therewith in a simple manner withconstant gear housing or like dimensions of the gear componentintermediate off-drives, or all-wheel off-drives can be achieved. Theassembling occurs only from one side and, namely, in the caserepresented, from the side of the cover 42. The assembling is simple inform and can be executed within the shortest time. The individualplanetary wheel sets can be exchanged among one another in respect totheir arrangements. Further, different off-drive variants are possible.

The axial fixing into position of the individual gear elements occursthere by security means, for example in the form of security rings 64 orstops 67. Besides the outer lamellae there are also governed so-calledpartitions 44, 45, 46 and 47. Further there occurs, likewise over theguide elements 40.1 to 40.4, the fixed arrangement or supporting of gearelements, for example lamellae carriers or the like.

FIG. 2 explains a cross section corresponding to a view A—A according toFIG. 1. There is evident the gear housing 11, which can be subdivided inthe case represented into two partial zones 50 and 51. The first partialzone 50 forms there in installation position the upper housing part, thesecond partial zone forms the housing part arranged underneath the gearsymmetry axis S in installation position. The gear housing 11 has, asalready explained in the statements for FIG. 1, a substantiallycylindrical inner contour 53, which encloses an interior space 41. Theinner contour 53 can be described by the diameter d₁. This extends asalready thoroughly explained in the statements for FIG. 1, essentiallyover the entire axial extent of the mechanical gear part 4.

Means are provided for the reception and binding-on of the gear elementsin radial direction, and for the security with respect to twisting incircumferential direction. These means are formed by the guide elements40.1 to 40.4. These are allocated to the inner circumference 53described by the diameter d₁ in such manner that these in installationposition of the gear unit 1, are arranged at a height H1 to H4 which, inrespect to the dimensions, is less than the dimension H5 described bythe maximal extent of the inner contour 53 in installation position inelevation direction. The guide elements, therefore, as explained in FIG.2, are arranged in the corner zones 54, 55, 56 and 57 of the housing 11,the corner zones so that they make it possible to describe an allocationof a quadrate or rectangle to the inner contour 53. The corner zones 54to 57 are described there in installation by allocation of the quadrate(square) Q_(theoretical) in which the diameter d₁ circumscribed by theinner contour is arranged in the quadrate and both, the theoreticalquadrate Q_(theoretical) cited for consideration, as well as the innerdiameter d of the inner contour 53 of the housing, have the samesymmetry axes S1 and S2, respectively.

For the reception of the guide elements, corresponding recesses areprovided in the housing. These are designated here in each case with60.1 to 60.4 for the individual guide elements. The arrangement of theserecesses 60.1 to 60.4 in the housing occurs there outside of a range onthe gear housing which is described by, the respective symmetry of thegear component axis in elevational and in width direction, respectively,i.e, with use of a substantially rectangular housing outer form and anessentially cylindrical housing inner contour 53, only thematerial-intensive corner zones 54 to 57 of the housing 11 are used forthe reception of the guide elements 40.1 to 40.4. Additionalconstruction space in elevational or width direction is not needed. Theinterior space 41 can be formed with the maximally possible diameter d₁,since in height and width directions no additional construction spacehas to be provided for the tying-on of the gear elements. The gearhousing 11 itself can be equipped with a relatively thin housing wall inthe zones free from the worked-in recesses 60.1 to 60.4.

The recesses 60.1 to 60.3 form so-called engagement pockets into whichthe guide elements 40.1 to 40.4 can be inserted. Preferably in each casein axial direction, as explained in FIG. 1, there is provided apossibility for the suspension or for the floating bearing of the guideelements 40.1 to 40.4. This is designated in FIG. 1 with 62. Inaddition, the guide elements can also be guided in the partitions whichextend over the entire interior space in radial direction. FIG. 2explains, for example, the tying-on of the friction surface-carryingelement B₃₁. For the attaching to the guide elements 40.1 to 40.4, inFIG. 2 four possible variants of execution are represented,schematically simplified. Preferably for the axial fixing into positionof an elements there are used equal axial security elements. On theguide element 40.1 the axial securing occurs by use of shims, in theguide element 40.3 by means of a security ring 64 and on the guideelement 40.4 by sleeves 65.

For the threading of the individual gear elements onto the bar-formguide elements 40.1 to 40.4, the individual gear elements havecorresponding passage openings 66. Preferably the gear elements areconstructed in such manner that these have projections 63 in addition totheir circular cross section, on which projections there are alsorecesses or passage openings 66. This offers the advantage that theremaining construction space, especially the cylindrical interior space41 can be, essentially fully utilized and contains no additionaltroublesome elements. Especially in the attaching of the outer lamellaein correspondence to FIG. 2, for the force transfer a surface can beused which corresponds essentially to the surface describable by theinner diameter d₁.

Preferably the attaching of the gear elements occurs in all fourpossible corner zones 54 to 57. The guide elements 40.1 to 40.4 and thecorresponding projections on the gear elements are arranged withconstance spacing viewed in circumferential direction with respect tothe inner contour 53 of the gear component 1. There exists, however,also the possibility of finding a substantially symmetrical arrangementwhich differs from the arrangement in the corner zone. Further, it isnot compulsorily necessary to perform an attachment in all four cornerzones. For the twist safeguarding in circumferential direction at leasttwo guide elements are required.

Preferably the braking arrangements B1 to B4 are equipped with a devicefor the resetting of actuating elements. For this purpose, between ineach case two friction surface-carrying elements adjacent to oneanother, a spring storage unit is provided which according to FIG. 1 islikewise guided by the guide elements, to the guide element 40.1, and(which) is pre-tensionable, on generation of the frictional closurebetween the friction surface-carrying elements and the intermediateelement. In the case represented, between the friction surface-carryingelements of the braking arrangement B₁, there are provided a springstorage unit F₁or B₂, F₂, B₃-F₃ and B₄, F₄, respectively. The springstorage units there are always arranged outside of the frictionsurface-carrying intermediate elements, so that in this respect nocollision of any kind can arise between the spring storage units and thefriction surface-carrying intermediate elements. Preferably at leastbetween the first two friction surface-carrying elements adjacent to oneanother in force flow direction of a braking arrangement, correspondingspring storage arrangements are arranged. This execution offers theadvantage that by reason of the action of the spring storage unit,between the individual friction surface-carrying elements forcesdirected oppositely to these act in each case, so that a rapidseparation becomes possible with complete dissolving of the frictionclosure. The spring storage arrangement acts, therefore, at leastindirectly over the friction surface-carrying elements on the actuatingelement, in particular (on) a piston. The actuating elements, i.e. thepistons, can be acted upon, for example, hydraulically or pneumatically.The individual friction surface-carrying elements and the intermediateelements then no longer have to become released (sich freikleiden).There always occurs a forced separation by compulsion, at least in thezone in which the spring storage element is arranged.

The arrangement of the spring storage units between the individualfriction surface-carrying elements offers, further, the advantage thatthe dimensions of the friction surface-carrying elements in radialdirection are no longer dependent, because of the size of the interiordimensions of the gear housing under consideration, on the requisiteconstruction space of the device for the at least indirect resetting ofactuating elements. The arrangement of the spring storage units betweenthe friction surface-carrying elements, connectable with one anotherunder friction closure over an intermediate element offers, further, theadvantage of a space-saving execution of the resetting device in axialdirection, which again has a positive effect on the gear constructionlength.

The solution according to the invention is not restricted to one geartype as described in FIG. 1, but for this type of gears it offers anespecially advantageous possibility of assembling, which also by reasonof the exchangeability of individual gear elements as viewed in axialdirection, results in a universal usability of a certain basic geartype.

What is claimed is:
 1. A gear constructional unit comprising: a gearhousing having a cylindrical interior space for the reception ofindividual gear elements; and at least two bar-form guide elements whichextend, as viewed in an axial direction, over at least a part of theaxial extent of said cylindrical interior space, said guide elementshaving thereon bearings for a plurality of gear elements arranged infixed position with respect to said housing; said bar-form guideelements disposed in a space outside of a zone of the greatest heightdimension of said cylindrical interior space, as viewed when orientedfor installation; said bar-form guide elements being arranged inrecesses in said gear housing which are connected with said interiorspace.
 2. The gear constructional unit according to claim 1, whereinsaid bar-form guide elements are disposed in a zone which is bounded bythe least and the greatest height dimensions of the cylindrical interiorspace, as viewed when oriented for installation.
 3. The gearconstructional unit according to claim 1, wherein said gear housingcircumscribes a rectangular form and said bar-form guide elements arelocated in corner zones which are defined by the sections between saidinterior space and a theoretically constructed quadrate having sidedimensions greater than or equal to the diameter of said interior space,said theoretically constructed quadrate and said interior space havingidentical axes of symmetry.
 4. The gear constructional unit according toclaim 3, wherein said bar-form guide elements are arranged in all fourcorner zones and have circumferentially equal spacing.
 5. The gearconstructional unit according to claim 1, wherein said individual gearelements guided on said bar-form guide elements include projectionshaving passage openings for the reception of said bar-form element, saidpassage opening formed in such manner that said projections are receivedby said recesses in said gear housing.
 6. The gear constructional unitaccording to claim 1, further comprising means which limit the movementof said gear elements in an axial direction.
 7. The gear constructionalunit according to claim 6, wherein said means comprise security-rings.8. The gear constructional unit according to claim 5, wherein said meanscomprise sleeve-form elements.
 9. The gear constructional unit accordingto claim 5, wherein said means comprise stop surfaces formed by saidindividual gear elements.
 10. The gear constructional unit according toclaim 1, wherein said inside diameter of said cylindrical interior spaceis constant over at least a portion of the axial extent of saidcylindrical interior space.
 11. The gear constructional unit accordingto claim 1, further comprising: a mechanical gear part; and ahydrodynamic gear part; wherein said cylindrical interior space of saidgear housing has a constant diameter as viewed in an axial direction atleast over the range of said mechanical gear part.
 12. The gearconstructional unit according to claim 1, wherein: at least one gearelement forms a partition; and said bar-form guide elements are mountedin said partitions.
 13. The gear constructional unit according to claim1, wherein at least one bar-form guide element is mounted such that itis suspended at least in said gear housing.
 14. The gear constructionalunit according to claim 1, further comprising: at least one gear elementin the form of a lamellar braking arrangement, comprising at least twofriction surface-carrying elements, said friction surfaces compressed byone another through a further friction surface-carrying intermediateelement; and at least one spring storage unit between two adjacentfriction surface-carrying elements, said spring storage unit guided bysaid bar-form guide elements, and upon generation of the frictionalclosure said spring storage unit is preloaded between said frictionsurface-carrying elements and said intermediate element.
 15. The gearconstructional unit according to claim 1, wherein said bar-form guideelement is a solid element.
 16. The gear constructional unit accordingto claim 1, wherein said bar-form guide element has at least a portionthat is hollow.
 17. The gear constructional unit according to claim 1,wherein said bar-form guide elements function as axles.